Surgical therapy of aortic diseases (aortic aneurysm, aortic dissection, etc.) involves replacing the diseased aortic part with an artificial blood vessel. Especially, in the case of treatment of a wide range from the aortic arch to the descending aorta, an aortic arch replacement surgery is performed. This surgical operation uses an operative system (also called “frozen elephant trunk technique”) wherein the aortic arch is trimmed, an artificial blood vessel provided with a stent at one end portion (an artificial blood vessel having a metallic skeleton for retaining a tubular form; also called “stent graft”) is inserted into the living body blood vessel to reach the descending aorta, and the stent is pressed against the blood vessel wall. Thereafter an intermediate portion of the artificial blood vessel and the trimmed portion of the aortic arch (or descending aorta) are anastomosed with each other, and, further, the artificial blood vessel is anastomosed with other arteries. An example of this surgical operation is described in U.S. Pat. No. 6,773,457.
In the aortic arch replacement surgery, conventionally the anastomosis between the intermediate portion of the artificial blood vessel and the aortic arch includes a work in which, as shown in FIG. 4 of U.S. Pat. No. 6,773,457, the other end portion of the artificial blood vessel on the side where the stent is not provided (the artificial blood vessel section on this side is referred also to “tube” in contrast to the stent) is folded back to the inside (this work is also called “introversion”). This ensures that the folded end portion of the tube and the trimmed end portion of the aortic arch are anastomosed with each other comparatively easily and reliably. Consequently, the surgical operation time is shortened, and, further, the burden on the patient is alleviated.
The aortic arch replacement surgery normally involves only a thoracic midline incision to reduce the operative invasion exerted on the patient. As a result, the operative steps such as stent insertion, tube-artery anastomosis, etc. as mentioned above have to be carried out within a narrow operative region.
With such a narrow region, however, it is difficult to smoothly fold back the other end portion of the tube to the inside of the tube itself. Specifically, when attempts are made to fold back the tube to a desired position (folded end portion), a pushing-in force attendant on the folding-back work would cause the tube to be pushed into the aortic arch or the descending aorta, probably making it impossible for the tube to be folded back into the inside thereof in a desired shape. Consequently, the folding-back work becomes very troublesome, the working efficiency of replacement surgery is lowered, and the burden on the patient is increased considerably.